(a) Field of the Invention
The present invention relates generally to a distribution system and a method of operating the same and, more particularly, to a substrate distribution system for manufacturing a liquid crystal display (LCD).
(b) Description of the Related Art
Liquid crystal displays (LCDs) have become one of the most widely used flat panel displays. Generally, an LCD includes a pair of panels individually having electrodes on their inner surfaces, and a dielectric anisotropy liquid crystal layer interposed between the panels. Varying the voltage difference between the field generating electrodes, i.e., varying the strength of an electric field generated by the electrodes, changes the transmittance of the light passing through the LCD, and thus desired images may be obtained by controlling the voltage difference between the electrodes.
An LCD manufacturing process includes three main processes: a panel manufacturing process, a cell manufacturing process, and a module process.
The panel manufacturing process produces thin film transistor (TFT) panels and color filter panels using treated glass substrates. In more detail, in one example of the TFT panel manufacturing process, a plurality of TFTs and a plurality of pixel electrodes are formed on the lower panel. In one example of the color filter panel manufacturing process, dye or pigment filter materials of red (R), green (G), and blue (B) are deposited on the inside of the upper panel having a black matrix to form R, G, and B color filter layers, and indium tin oxide (ITO) material is also deposited on the interior of the upper panel to form common electrodes.
The cell manufacturing process includes several process steps. First, in order to create a uniform distance between both glass panels, spacers are sprayed on one panel. Then, the TFT panel and the color filter panel are combined to form a panel assembly, which is divided into a plurality of cells. Each cell is then filled with liquid crystal.
The module process forms circuitry for signal processing and connects the circuitry to the panels, thereby completing a module.
The cell manufacturing process includes cutting of a large-size mother panel. That is, the mother panel is scribed and cut into a plurality of cells having final display dimensions by a scribing process. After the scribing process, the cells are distributed to a subsequent grinding process.
However, as the number of cells cut from one mother panel increases, the distribution system has a serious bottleneck problem as the tact time of the scribing system becomes smaller than that of the distribution system. Also, as the manufacturing process of the LCD proceeds, the difference between the tact times of the two systems is continuously accumulated, causing a more serious bottleneck.
Furthermore, since the number of cells cut from a mother panel may increase as the panel size becomes larger, bottleneck becomes a more serious concern in this case. Also, as the manufacturing equipment becomes larger, the transfer distance of the transfer device increases, so that the bottleneck becomes more serious.
Therefore, as improved distribution system and method of operating the same are highly desirable.